Keep tagged schema-2 registries readable after backport retirement

Signed-off-by: Ralf W. Grosse-Kunstleve <rgrossekunst@nvidia.com>

Author: rwgk

ci/tools/bindings_config.py

@@ -188,14 +188,25 @@ def _validate_release_statuses(packages: tuple[BindingsPackage, ...]) -> None:
 
 
 def validate_config(raw: Any) -> BindingsConfig:
-    root = _mapping(raw, "versions configuration", {"schema_version", "cuda", "python"})
+    root = _mapping(raw, "versions configuration")
+    root_keys = {"schema_version", "cuda", "python"}
+    # Earlier schema-2 release tags retain this field; keep reading their
+    # registries after the active backport workflow stops using it.
+    if "backport_branch" in root:
+        root_keys.add("backport_branch")
+    _mapping(root, "versions configuration", root_keys)
     if type(root["schema_version"]) is not int or root["schema_version"] != SCHEMA_VERSION:
         raise BindingsConfigError(f"schema_version must be {SCHEMA_VERSION}")
     cuda = _mapping(root["cuda"], "cuda", {"bindings"})
     bindings = _mapping(cuda["bindings"], "cuda.bindings", {"package_roots"})
     raw_package_roots = _mapping(bindings["package_roots"], "cuda.bindings.package_roots")
     packages = tuple(_package(package_root, value) for package_root, value in raw_package_roots.items())
     _validate_release_statuses(packages)
+    if "backport_branch" in root:
+        maintenance = next(package for package in packages if package.release_status == "maintenance")
+        expected_branch = f"{maintenance.ctk_target}.x"
+        if root["backport_branch"] != expected_branch:
+            raise BindingsConfigError(f"backport_branch must match maintenance CUDA line {expected_branch!r}")
     cuda_majors = [package.cuda_major for package in packages]
     if len(set(cuda_majors)) != len(cuda_majors):
         raise BindingsConfigError("CUDA bindings cuda_major values must be unique")

ci/tools/tests/test_bindings_config.py

@@ -133,6 +133,47 @@ def test_registry_validation_rejects_invalid_schema_and_release_layout(change, m
         validate_config(data)
 
 
+@pytest.mark.parametrize("toolkit_version", ("12.9.1", "12.8.4"))
+@pytest.mark.agent_authored(model="gpt-6.1-sol")
+def test_backport_branch_agrees_with_the_maintenance_toolkit_line(toolkit_version):
+    data = _registry()
+    data["cuda"]["bindings"]["package_roots"]["cuda_bindings_12"]["toolkit_version"] = toolkit_version
+    data["backport_branch"] = ".".join(toolkit_version.split(".")[:2]) + ".x"
+
+    config = validate_config(data)
+
+    assert data["backport_branch"] == f"{config.package_for_release_status('maintenance').ctk_target}.x"
+
+
+@pytest.mark.parametrize("branch", ("13.4.x", "12.8.x", "12.9", "", None, True))
+@pytest.mark.agent_authored(model="gpt-6.1-sol")
+def test_registry_rejects_backport_branches_outside_the_maintenance_line(branch):
+    data = _registry()
+    data["backport_branch"] = branch
+
+    with pytest.raises(BindingsConfigError, match="backport_branch must match maintenance CUDA line '12.9.x'"):
+        validate_config(data)
+
+
+@pytest.mark.agent_authored(model="gpt-6.1-sol")
+def test_registry_accepts_no_legacy_backport_branch():
+    data = _registry()
+
+    config = validate_config(data)
+
+    assert config.package_for_release_status("maintenance").ctk_target == "12.9"
+
+
+@pytest.mark.agent_authored(model="gpt-6.1-sol")
+def test_registry_rejects_unknown_root_fields():
+    data = _registry()
+    data["backport_branch"] = "12.9.x"
+    data["unexpected"] = True
+
+    with pytest.raises(BindingsConfigError, match="must contain exactly"):
+        validate_config(data)
+
+
 @pytest.mark.agent_authored(model="gpt-6-sol")
 def test_registry_rejects_unknown_package_fields():
     data = _registry()
@@ -258,6 +299,46 @@ def test_bindings_release_uses_registry_from_its_tag_tree(
     }
 
 
+@pytest.mark.parametrize(
+    ("tag", "package_root", "toolkit_version", "release_version"),
+    (
+        ("v12.9.8", "tag-maintenance", "12.9.1", "12.9.8"),
+        ("v13.4.2rc1", "tag-current", "13.4.1", "13.4.2rc1"),
+        ("cuda-core-v1.2.0", "tag-current", "13.4.1", None),
+        ("cuda-pathfinder-v1.1.0", "tag-current", "13.4.1", None),
+    ),
+)
+@pytest.mark.agent_authored(model="gpt-6.1-sol")
+def test_release_cli_accepts_tagged_schema_two_registry_with_legacy_backport_branch(
+    tmp_path, capsys, tag, package_root, toolkit_version, release_version
+):
+    release_root = tmp_path / "release"
+    registry = _registry("tag-maintenance", "tag-current")
+    registry["backport_branch"] = "12.9.x"
+    _write_config(release_root, registry)
+    control_root = tmp_path / "control"
+    _write_config(control_root, _registry("control-maintenance", "control-current"))
+
+    assert (
+        main(
+            [
+                "--config",
+                str(control_root / "ci" / "versions.yml"),
+                "--release-tag",
+                tag,
+                "--release-source-root",
+                str(release_root),
+            ]
+        )
+        == 0
+    )
+
+    expected = {"package_root": package_root, "toolkit_version": toolkit_version}
+    if release_version is not None:
+        expected["release_version"] = release_version
+    assert json.loads(capsys.readouterr().out) == expected
+
+
 @pytest.mark.parametrize("tag", ("cuda-core-v1.2.0", "cuda-pathfinder-v1.1.0"))
 @pytest.mark.agent_authored(model="gpt-6-sol")
 def test_component_release_uses_current_bindings_from_its_tag_tree(tmp_path, tag):